Syrian government aircraft today pounded a rebel-held city in the country's northeast, killing at least 13 people including five children, activists said.
In northern Syria, meanwhile, a newly formed Islamist coalition of rebel brigades took control of a major crossing point with Turkey from the Western-backed Free Syrian Army, activists said.
The Britain-based Syrian Observatory for Human Rights said the air raids, eight strikes in total, hit the northeastern city of Raqqa early afternoon. Four women were among the dead and dozens of people were wounded, the Observatory said.
Rebels captured Raqqa, the capital of the province of the same name, in March. It's the only major urban center to fall entirely under opposition control since the Syrian conflict began in March 2011.
Rebels also control territory in the north and parts of Aleppo, Syria's largest city and its commercial center.
President Bashar Assad's forces have relied heavily on air power in the last year to regain control of opposition-held territory, particularly in the north and along the border with Turkey.
Last week, at least 50 people were reported killed in two helicopter attacks on a rebel-held town near Aleppo.
Activists say airstrikes often precede government ground offensives. Assad's troops may be mounting a major operation to recapture territory and bolster its position ahead of peace talks planned for January in Geneva.
Assad's control of Syria's skies is hampering rebels' efforts to hold on to territory they capture and administer it with any efficiency.
Infighting between rebel groups is another major factor that has weakened opposition forces in their fight to topple Assad's government.
The Observatory said fighters from the Islamic Front ousted the FSA from the Bab al-Hawa crossing point on Saturday, taking control over the administrative buildings and weapons' storage sites.
The Observatory did not report any violence during the takeover. There was no immediate confirmation of the development from the FSA commanders.
The Islamic Front formed last month, uniting rebel groups who say they want to transform Syria into an Islamic state after Assad's overthrow. Its formation is in part meant to stave off challenges from the more radical al-Qaida-linked Islamic State in Iraq and the Levant, which has emerged over the last year as one of the most effective fighting forces on the opposition side.
